vtab_media.Media

Module vtab_media :: Class Media

[show private | hide private]

Type Media

object --+    
         |    
ModuleBase --+
             |
            Media

Module to implements a virtual table that stores media data as native system files. The table has 2 fiels: __rowid__ and mediadata This class maintains its own rowid, cursor, and constraints parameters. The data of each row is stored in a file named Fxxxxxxx, where xxxxxxx is the rowid starting with 1 ie (F0000001, F0000002, etc)

Method Summary
	`__init__(self, pathname)`
	`BestIndex(self, constraints, orderby)` Provide information on how to best access this table.
	`Column(self, N)` Find the value for the N-th column of the current row.
	`Eof(self)` Determines if the current cursor points to a valid row.
	`filenamefromid(self, id)`
	`Filter(self, idxNum, idxStr, argv)` Begin a search of a virtual table.
	`getnextrowid(self)` Return the next row ID from a file called rowid
	`idfromfilename(self, filename)`
	`incrementrowid(self)`
	`Next(self)` Move the cursor to the next row.
	`Rowid(self)` Return the rowid of the current row.
	`saverowid(self, id)`
	`UpdateChangeRow(self, rowid, newrowid, fields)` Change the row of the current rowid with the new rowid and new values
	`UpdateDeleteRow(self, rowid)` Delete row rowid
	`UpdateInsertRow(self, rowid, fields)` Insert a new row of data into the table
Inherited from ModuleBase
	`Begin(self)`
	`Close(self)` Close a cursor previously created by Open By default, do nothing
	`Commit(self)`
	`Connect(self, connection, modulename, databasename, vtablename, *args)` Connect to an existing virtual table, by default it is identical to Create
	`Create(self, connection, modulename, databasename, vtablename, *args)` Called when the virtual table is created.
	`Destroy(self)` Release a connection to a virtual table and destroy the underlying table implementation.
	`Disconnect(self)` Release a connection to a virtual table.
	`Open(self)` Create/prepare a cursor used for subsequent reading.
	`Rollback(self)`
	`Sync(self)`
Inherited from object
	`__delattr__(...)` x.__delattr__('name') <==> del x.name
	`__getattribute__(...)` x.__getattribute__('name') <==> x.name
	`__hash__(x)` x.__hash__() <==> hash(x)
	`__new__(T, S, ...)` T.__new__(S, ...) -> a new object with type S, a subtype of T
	`__reduce__(...)` helper for pickle
	`__reduce_ex__(...)` helper for pickle
	`__repr__(x)` x.__repr__() <==> repr(x)
	`__setattr__(...)` x.__setattr__('name', value) <==> x.name = value
	`__str__(x)` x.__str__() <==> str(x)

Method Details

init(self, pathname)
(Constructor)

Overrides:: database.ModuleBase.__init__

BestIndex(self, constraints, orderby)

Provide information on how to best access this table.
Must be overriden by subclass.
@params constraints: a tuple of (column #, op) defining a constraints
@params orderby: a tuple of (column #, desc) defining the order by
@returns a tuple of up to 5 values:
    0: aConstraingUsage: a tuple of the same size as constraints.
        Each item is either None, argv index(int), or (argv index, omit(Bool)).
    1: idxNum(int)
    2: idxStr(string)
    3: orderByConsumed(Bool)
    4: estimatedCost(float)

Todo: store the constraints for subsequent evaluation, and tell
    sqlite to pass the constraints parameters to Filter.